Plasticity of GABA_B receptor-mediated heterosynaptic interactions at mossy fibers after status epilepticus

Research output: Contribution to journalArticle

Authors

  • K Chandler
  • R Fabian-Fine
  • DM Kullmann
  • MC Walker

Colleges, School and Institutes

Abstract

Several neurotransmitters, including GABA acting at presynaptic GABA(B) receptors, modulate glutamate release at synapses between hippocampal mossy fibers and CA3 pyramidal neurons. This phenomenon gates excitation of the hippocampus and may therefore prevent limbic seizure propagation. Here we report that status epilepticus, triggered by either perforant path stimulation or pilocarpine administration, was followed 24 hr later by a loss of GABA(B) receptor-mediated heterosynaptic depression among populations of mossy fibers. This was accompanied by a decrease in the sensitivity of mossy fiber transmission to the exogenous GABA(B) receptor agonist baclofen. Autoradiography revealed a reduction in GABA(B) receptor binding in the stratum lucidum after status epilepticus. Failure of GABA(B) receptor-mediated modulation of mossy fiber transmission at mossy fibers may contribute to the development of spontaneous seizures after status epilepticus.

Details

Original languageEnglish
Pages (from-to)11382-11391
Number of pages10
JournalThe Journal of Neuroscience
Volume23
Issue number36
Publication statusPublished - 1 Jan 2003

Keywords

  • epilepsy, GABA(B) receptor, status epilepticus, seizures, mossy fibers, CA3